Peppercorns, whether black, white or green, are the dried fruits of the pepper plant (Piper nigrum) of the Piperaceae family. The evergreen pepper plant is a woody climber, which grows up to 4 m high on stakes. Its fruits are in spikes (up to 15 cm long) of 20 – 30 stone fruits, which change color from green to yellow to red during ripening. The initially green and later red berries contain a seed surrounded by a thin fruit wall. The pepper plant is indigenous to Malabar and is cultivated in all tropical countries.
The term spice is used to refer to plant parts which serve to improve the odor and flavor of foods. They contain Essential Oils and other ingredients which have a strong seasoning action. Spices are processed, cleaned, graded and carefully packaged for overseas dispatch in the countries where they are cultivated. They are dried to preserve them for transport and storage. In consumer countries, they are delivered to spice mills, where they are cleaned and graded again, ready for sale in unground or ground form.
Spices are classified by the plant parts used:
- Fruit and seed spices (e.g. pepper, cardamom, nutmeg)
- Bud and flower spices (e.g. cloves)
- Bark spices (e.g. cinnamon)
- Root spices (ginger, turmeric)
- Leaf spices (bay leaf)
Green pepper is produced by washing the fully grown, but still green berries in brine straight after harvesting, so preventing the color change to brown caused by oxidation. Pepper is increasingly also being imported into Germany in this form/color. The peppercorns are frequently offered for sale in freeze-dried form.
A substantially larger proportion is, however, imported in the form of white and black pepper, which are also obtained from the pepper plant (Piper nigrum). The unripe, unpeeled, dried, wrinkly fruits of a size of 3 – 6 mm are known as black pepper, while white pepper is obtained from the fully ripe fruit by removing (peeling) the outer pericarp after 2 – 3 days’ fermentation and drying the seeds to yield smooth, yellow to dirty yellow peppercorns of a size of 2 – 4 mm. White pepper has a higher content of piperine (C17H19NO3) and consequently has a hotter taste than black pepper. Fresh peppercorns contain approx. 5 – 9% piperine.
- 4.6 – 9.7% piperine in black pepper
- 4.8 – 10% piperine in white pepper
Next to salt (NaCl), pepper is the most widely used condiment. It is used domestically and in the food industry. The piperine present in pepper has an antiinflammatory, antipyretic and diaphoretic action.
Storage / transport
Pepper is a very valuable spice. The various types of pepper should have the following appearance:
- White pepper: yellow to dirty yellow
- Tellicherry pepper, Malabar pepper: dark brown to black, netted, spherical, hard, heavy
- Lampong pepper, Sarawak pepper, Cambodia pepper: brownish to black, uneven, not markedly netted, spherical
Provided that recommended storage conditions are maintained, black and white pepper may generally be stored for a period of up to 24 months. Pepper is transported inter alia in new double-layered bags (e.g. 50 kg, 63.5 kg, 72.5 kg or 84.5 kg) as well as in flat jute fabric bags (e.g. 71.6 kg).
The following types of containers are suitable:
- Open-sided container with tarpaulins, which are rolled up during transport, so ensuring active ventilation by the ship’s ventilation plant.
- Passively ventilated container (ventilated container or coffee container). Ideally: actively ventilated container (closed, ventilated container with mechanical ventilation system)
- Thermally insulated refrigerated container with fresh air supply
For all the recommended container types, it is important to pay proper attention to ventilation. Stowing system for pepper bags in containers, see RF Ventilation. In damp weather (rain, snow), the cargo must be protected from moisture, since this may lead to mold, spoilage and self-heating. No hooks should be used with bagged cargo, so as to prevent damage to the bags and loss of volume. Stow cool, dry with good ventilation. Containers should be stowed below deck away from sources of heat because there is a risk of self-heating and, for white pepper, a risk of post-fermentation. Open-sided containers must be stowed below deck: due to the rolled up tarpaulins, the bags are unprotected but must be protected from rain and spray.
In order to ensure safe transport, the bags must be stowed and secured in the means of transport in such a manner that they cannot slip or shift during transport. If loss of volume and degradation of quality are to be avoided, the packages must not be damaged by other articles or items of cargo. Attention must also be paid to stowage patterns which may be required as a result of special considerations, such as ventilation measures.
Pepper requires particular temperature, humidity/moisture and ventilated conditions. Favorable travel temperature range: 5 – 25°C. Dried pepper should be transported in areas which exhibit the lowest temperatures during the voyage and are dry. In any event, storage beneath the weather deck or, in the case of shipping in containers, in the uppermost layer on deck, must be avoided as the deck or container is strongly heated by the intense tropical sun and, at temperatures of > 25°C, essential oils may be lost and there is a risk of self-heating. At temperatures of > 40°C, the product dries out by > 0.5%. If a container is exposed to direct solar radiation, the product may dry out by up to 2% or more.
In the hotter parts of the year, the temperature difference between the port of loading and unloading may be 15 – 20°C. In the colder parts of the year, however, it is > 30°C. Incoming cold air may cause sudden drops in temperature which, especially in container interiors, may result in a considerable increase in relative humidity. In this situation, a low product water content is of vital significance: the higher is the product water content, the higher is the equilibrium moisture content, i.e. the relative humidity of the container air.
If the relative humidity of the container air increases, so too does its dew point. At relative humidity levels of < 100%, the dew point is below air temperature (example: air temperature = 25°C and relative humidity = 70% -> dew point = 19°C). However, if relative humidity (relative humidity = ratio of absolute to maximum humidity) reaches a value of 100%, the dew point is the same as the air temperature and condensation occurs. Corresponding values may be obtained from Climate/humidity tables. A rapid and major drop in external air temperature can easily reduce the temperature of the container walls/ceiling to below the dew point of the internal air. This results in the formation of condensation on the internal surfaces of the container which drips onto the cargo and may cause damage (wetness, mold, self-heating).
Humidity / Moisture
|Relative Humidity||50 – 60%|
|Water content||10 – 15%|
|Maximum equilibrium moisture content||55%|
Pepper releases large quantities of water vapor, with black pepper releasing larger quantities of water vapor than white pepper. The fresh commodity in particular releases large quantities of water vapor and should not be stowed in a hold or container together with moisture-sensitive products. Pepper is very moisture-sensitive. The water content of the product should always be < 15%. An ideal moisture content on loading is 10 – 11%, as a result of which it is possible to prevent both moisture damage and the development of insect pests.
Pepper is strongly hygroscopic (hygroscopicity), which is characterized by the steep gradient of the sorption isotherm. At the admissible upper limit for water content of 15%, pepper has an equilibrium moisture content of 55%; at 70% the water content of pepper is already 19%. Packaging in jute bags, which are also strongly hygroscopic, does not alleviate the problem: even at a water content of 9%, the critical point for jute fabric is at an equilibrium moisture content of 65%. If the product is wetted by seawater, rain or condensation, it must be dried immediately, otherwise there is a risk that the pepper will decompose and the jute bags rot.
Particular care must be taken when loading containers during the monsoon season, as humidity is extremely high at this time. In order to prevent condensation on the ship’s side or container walls from affecting the cargo, care should be taken to leave a clear gap between the cargo stack and the ship’s side or container wall. The product should also be covered with mats or cloths which are capable of briefly absorbing any condensation which may drip onto the cargo. It is also possible to apply an “anticondensation” film or to coat the inside of the container with moisture-absorbing paints (which provide protection for only a limited time).
Pepper requires particular temperature, humidity/moisture and ventilation conditions. Recommended ventilation conditions: air exchange rate 10 changes/hour. If ventilation is inadequate, vaporization of the residual intrinsic moisture content may rapidly result in moisture damage by sweating. In order to avoid formation of mold and self-heating, the stowage space should be cool, dry and, most particularly, easy to ventilate.
Container transport: stowage space below deck must permit sufficient air flow around and through the containers to achieve continuous airing, especially for naturally ventilated containers. In this case, a minimum air exchange rate of 20 changes/hour is recommended in the hold, but only 10 – 20 changes/hour for open-sided containers, as drying losses must otherwise be expected.
Ventilation of the hold in a container ship must be arranged such that the “chimney” effect is achieved with the air being blown in from beneath and rising upwards through the layers of containers, so continuously removing warm, moist air.In the event of a rapid drop in external air temperature, any consequent impact upon the holds and thus upon the containers may be alleviated by reducing or completely ceasing ventilation. In the case of major drops in temperature in the hold air, it is primarily the ceilings and free walls of the container which cool down, such that increased condensation must be expected on these surfaces where the air above the cargo has a relatively high water vapor content, as occurs in the case of products with an elevated water content.
It is also important to strip (unpack) the containers quickly on arrival at the port of destination. Especially at the cooler times of year, when the containers are removed from the relatively protected environment of the ship’s hold and are exposed to the sometimes considerably lower temperature of the outside air, the relative humidity in the containers may rise rapidly, resulting in condensation. For this reason, the containers should be stripped (unpacked) or at least placed in protected storage immediately on arrival at the port of discharge.
In order to ensure more effective airing of the pepper bags stowed in the container, a particular stowage pattern, similar to that for coffee or cocoa, should be used:
- Two layers of bags are first laid crosswise in two stacks, with some space being left at the side walls (important, so that the ventilation openings in the floor are not blocked up). Free space, which should usually be of a size of 20 – 30 cm, is also left in the middle in order to provide a ventilation channel.
- A layer is then stowed lengthwise on the second layer.
- The next layer is again stowed crosswise, bridging the gap between the two stacks with one bag.
- Stowing is continued in this manner until the container is full. Approx. 50 – 75 cm of free space must remain between the uppermost layer and the container roof in order to ensure free circulation of fresh air supplied from outside.
- Free space (approx. 10 – 15 cm) must also remain between the container door and the stowed bags so that the necessary air circulation can be maintained here as well. The bags in the door area must be secured with lashings so that they do not slip into this free space in transit, which would block air circulation.
Pepper displays 3rd order biotic activity. It is among those products in which respiration processes are suspended. Nevertheless, biochemical, microbial and other decomposition processes still proceed in such products and must be taken into consideration.
Due to continuing fermentation processes, an increased CO2 concentration and a consequent O2 shortage may occur in the hold. No-one should enter the hold until it has been ventilated and, if necessary, a gas measurement performed with a gas detector.
Self-heating / Spontaneous combustion
Where ventilation is inadequate and the water content excessively high (e.g. in the case of excessively fresh pepper), pepper undergoes spoilage by self-heating; it then becomes completely wet, swells and heats up so much that it begins to steam, as a result of which the cargo may become completely worthless within a very short time. In the case of white pepper, there is the risk of post-fermentation. The risk of self-heating is further increased by excessively high storage temperatures.
- 4.6 – 9.7% piperine in black pepper
- 4.8 – 10% piperine in white pepper
Active behavior: Dried pepper has a strong, pleasant and characteristic odor which is attributable to the content of essential oils (e.g. piperine, piperidine and the resin chavicine). An increase in odor in the container or hold indicates self-heating, increased release of water vapor and the loss of essential oils. When transporting spices, it is important to retain the content of essential oils to the greatest possible extent, since these substances, together with other constituents, such as fatty oils, tannins and bitter principles, determine the odor and flavor and thus quality of the spices. The essential oils are readily volatilized and the seasoning action of the spices is consequently reduced. Volatilization of the essential oils is primarily determined by temperature. The higher is the ambient temperature, the more the essential oils are volatilized, as may be recognized by the intense odor in the hold. Due to the readily volatilized essential oils, spices should be stowed separately from each other and away from foodstuffs which readily absorb foreign odors (e.g. coffee, tea or copra).
Passive behavior: Pepper is extremely odor-sensitive and should not be stowed together with strong-smelling products (e.g. extracts or essential oils).
Active behavior: Pepper does not cause contamination.
Passive behavior: Pepper is sensitive to contamination by dust, dirt, Fats and Oils. Black pepper may be contaminated by up to 1% admixed white pepper and vice versa.
Pepper bags are sensitive to mechanical stresses. No hooks should be used with bagged cargo (loss of volume).
Toxicity / Hazards to health
Pink pepper is toxic in large quantities.
Shrinkage / Shortage
Especially with fresh pepper, weight losses of up to 7% may occur by evaporation of residual intrinsic moisture content. Normal values are, however, between 1 and 2% for white pepper and 2 and 4% for black pepper. The product is highly valuable and is thus particularly at risk from theft.
Insect infestation / Diseases
In general, pepper is very rarely affected, but if it is, damage is mainly caused by small rodents or insects (e.g. beetles, moths or mites).
Additional information on peper
Black and white pepper are the dried fruits of the same plant. Black pepper comes from the unripe fruit and white pepper from the ripe, washed and peeled fruit. Usually shipped in double bags. Loss of weight through evaporation of moisture can be as much as 7% in the case of fresh pepper, but the normal is 1% to 2% for white and 2% to 4% for black pepper. Liable to heat and sweat with resultant mustiness and loss of value. To avoid mould and insect development pepper should be dried to 10% or 11% moisture content and packed in polythene-lined bags. Pepper can be kept for a number of years without damage, but by absorption of moisture may show signs of mould; this can be dispersed by washing and drying without lowering the quality of the pepper, provided it is not too badly affected.
A strongly respirating (sweating) cargo and good separation is required from the steelwork of the container. Do not stow black and white pepper together in the same container and do not stow together with delicate cargoes such as tea, or with heat-sensitive cargoes, copra, tapioca, gambier, onions, etc. In view of its high value, be aware of theft. Pay attention to warm bags during stuffing. An alternative to using a high vent container is to use a GP container and observe stowage as detailed for coffee and cocoa in bags, by lining with Kraft paper and inserting “Dry-Bag” desiccants.